I suspect the mechanic tossed out the warped head diagnosis to ensure it was understood that a resurface is mandatory for a good repair. The block deck needs to be checked for flatness, as does the head. I would be surprised to see a head that had a gasket failure, especially on an inline six, not show some surface irregularities.

It is a pretty easy fix. As mentioned parts are plentiful and inexpensive. I have seen several running motors in the $400-600 range recently. Depends on the condition of the rest of the car though, and the current owners lack of desire to make repairs I guess